1. Field of the Invention
The invention relates generally to a shelf for use in such a steam environment as a steam sterilizer and, more particularly, to a shelf for use in such a steam environment which is directed toward reducing the quantity of steam condensation that drips from the shelf.
2. Description of the Prior Art
Generally, a shelf used to support articles in such a steam environment as a steam sterilizer includes a plurality of solid rods or wires, usually made of metal, that are secured to apparatus for supporting the shelf within the steam environment.
One problem associated with the use of such a shelf is the condensation that forms on the shelf and drips onto the load supported by another shelf disposed below it. If, during a steam sterilization process, water drips onto such a load as a pack comprising articles to be sterilized that are wrapped in a permeable cloth, paper, or nonwoven material, the pack could absorb water. Such a load, commonly referred to as a "wet pack", is difficult to dry because it is not uniformly moist. If an incompletely dried sterile wet pack is removed from a sterile environment, the wet portion of the wrap might form a path along which bacteria could travel through the pack and contaminate the sterile articles. Thus, the sterilization cycle should include an extended drying period to dry any wet packs which may have been created during the cycle and ensure that the material inside the pack will remain sterile after the pack is removed from the sterilizer.
The problem identified above is caused by the relatively large quantity of condensation that forms on a shelf having solid metallic support rods or wires. The rods or wires must absorb a large amount of thermal energy from the surrounding steam before their temperature can rise to that of the environment. As thermal energy is transferred from the steam to the rods, some steam condenses and water forms on the rods. The greater the amount of energy required to raise the temperature of the rods to the temperature of the environment, the greater the amount of steam that must condense to supply the energy, and the greater the amount of water that is formed.
Accordingly, there is a need for a shelf for use in a steam environment that will inhibit the formation of condensation on the load supporting members of the shelf and that will prevent any condensation that does form on the members from dripping onto loads supported by other shelves.